One of conventional power conversion apparatuses is the following step-up AC-DC conversion circuit. A reactor is provided at a connection point between an AC power supply and a diode rectification circuit, a main switching device is connected between the output terminals of the diode rectification circuit, a series circuit including a capacitor and a diode is connected in parallel with the main switching device, and a pair of ends of the capacitor is a DC output. A bridge circuit including a capacitor, and two series circuits each of which includes a diode and a switching device connected in series, the capacitor and the two series circuits being connected in parallel, is provided between the diode rectification circuit and the main switching device, thereby reducing harmonics of an input current in the step-up AC-DC conversion circuit (for example, see Patent Literature 1).
Patent Literature 1: Japanese Laid-Open Patent Publication No. 2007-282442